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101.
M Kubo H Matsuda M Tanaka Y Kimura H Okuda M Higashino T Tani K Namba S Arichi 《Chemical & pharmaceutical bulletin》1984,32(7):2724-2729
102.
M. Takahashi H. Kuze H. Tashiro M. Takami S. Namba 《Applied physics. B, Lasers and optics》1986,41(2):91-94
The carbon-isotope selectivity in the multiphoton dissociation of CF3Br is studied in the collisional region of supersonic free jet. The isotopic abundance of12C and13C in C2F6 formed by recombination of the dissociation products is measured with a quadrupole mass spectrometer. An enrichmet factor of 9.4 is obtained for12C with the 9R(30)CO2 laser line while the factor of 6.9 is obtained for13C with the 9P(16) line. 相似文献
103.
104.
Stimulated emission has been observed at the M line (2.543 eV) in optically excited CdS crystals under an applied uniaxial stress perpendicular to the C axis at 4.2 K. This emission is strongly polarized with an electric vector parallel to the applied stress. The observed polarization characteristics are successfully accounted for by assuming a radiative annihilation of an excitonic molecule, providing an experimental evidence for ascribing this emission to the excitonic molecule in CdS. 相似文献
105.
Ashie Y Hosaka J Ishihara K Itow Y Kameda J Koshio Y Minamino A Mitsuda C Miura M Moriyama S Nakahata M Namba T Nambu R Obayashi Y Shiozawa M Suzuki Y Takeuchi Y Taki K Yamada S Ishitsuka M Kajita T Kaneyuki K Nakayama S Okada A Okumura K Ooyabu T Saji C Takenaga Y Desai S Kearns E Likhoded S Stone JL Sulak LR Walter CW Wang W Goldhaber M Casper D Cravens JP Gajewski W Kropp WR Liu DW Mine S Smy MB Sobel HW Sterner CW Vagins MR Ganezer KS Hill J Keig WE Jang JS Kim JY Lim IT Ellsworth RW 《Physical review letters》2004,93(10):101801
Muon neutrino disappearance probability as a function of neutrino flight length L over neutrino energy E was studied. A dip in the L/E distribution was observed in the data, as predicted from the sinusoidal flavor transition probability of neutrino oscillation. The observed L/E distribution constrained nu(micro)<-->nu(tau) neutrino oscillation parameters; 1.9x10(-3)0.90 at 90% confidence level. 相似文献
106.
107.
Lourenzoni MR Namba AM Caseli L Degrève L Zaniquelli ME 《The journal of physical chemistry. B》2007,111(38):11318-11329
The HNP-1, HNP-2, and HNP-3 defensins are human antimicrobial peptides produced in response to microbial invasion. Their properties are distinct, with a more potent action for HNP-3. In this study, the relationship between their structural dissimilarities and their different microbial actions was evaluated by molecular dynamics simulation. Structural determinants related to their intra- and intermolecular interactions were defined for each HNP using a simplified membrane model consisting of a water/n-hexane interface. The hydrophobic portion of the HNPs promotes their diffusion to the interface with a concomitant, slight change in the structure induced by the intermolecular electrostatic interactions between the HPN molecules and the interface. As a consequence, different orientations are probably adopted by the HNPs at the interface, which may explain their different actions. The interaction of HNP-1 and HNP-2 with the surfaces was also studied using Langmuir monolayers as a biomimetic system. It was found that peptides adsorb rapidly at n-hexane/water interfaces as well as at phospholipid Langmuir monolayers but not at the air/liquid interface. This reveals that the presence of an organic phase is required for the exposure of the hydrophobic groups of the peptides. In addition, adsorption kinetics and surface pressure-area isotherms for Langmuir monolayers suggested that the lipid-peptide interaction is strongly influenced by the monolayer electrical charge and packing, depending also on the HPN structure. This study supports a model in which defensins, acting in a dimeric form, are able to disrupt membranes. The model also shows that the individual structures of the HNPs are responsible for their different actions on microbes. 相似文献
108.
Yasufumi Ohfune Takashi DemuraSeiji Iwama Hiromi MatsudaKosuke Namba Keiko ShimamotoTetsuro Shinada 《Tetrahedron letters》2003,44(29):5431-5434
Efficient synthesis of (+)-2-aminobicyclo[3.1.0]hexane-2,6-dicarboxylic acid (LY354740: 1) and its structurally related analogs (−)-2 and (−)-3 has been accomplished starting with (1S,2R)-1-amino-2-hydroxycyclopentane- or cyclohexanecarboxylic acid (4 or 17 ) via an intramolecular cyclopropanation of α-diazo acetamide. 相似文献
109.
2,3-Naphthalimide derivatives incorporating trifluoroacetamido (3a) and methansulfonamido (3b) functionalities at the 1-position were prepared and their intramolecular excited state proton transfer (ESIPT) fluorescence and responses to metal ions were investigated. Compound 3a displayed normal fluorescence in the amide form in toluene and MeCN and no response to metal cations in the corresponding amidate ion form. In contrast, compound 3b gave off dual emission assignable to normal and ESIPT fluorescence. Additionally, the amidate form of compound 3b displayed off-on fluorescence response to Ca2+. 相似文献
110.